Over the next few decades the world’s energy systems will undergo a seismic revolution, with a transformation on a massive scale as renewable energy takes over from fossil fuels. This will be driven not only by the urgent imperative to address climate change, but also by the overwhelming economics of renewable energy.

This article examines the implications of the energy revolution for national security. The analysis is in three parts: the implications for the security of supply chains; the shift from a centralised energy generating system to a disseminated network of myriad energy sources; and the implications for cyber security.

The first and most marked change in theenergy security balance will be the shift away from traditional fuel supply lines, and the disappearance of dependence on foreign energy sources for many nations.

The ability to exploit indigenous renewable energy (including solar photovoltaics, wind, concentrated solar thermal, geothermal, wave and tidal generation) will mean nations rely less and less on imported fossil fuels such as coal, oil and gas.

The same is true of indigenous unconventional natural gas being unlocked by technological advances such as hydraulic fracturing (fracking). Further, those nations that have embraced nuclear power to address climate change can stockpile many years of high-energy- density uranium to improve supply chain security, compared with a continuous reliance on imported fossil fuels.

For some renewable energy rich nations, such as Australia, the cutting of the energy umbilical cord will be almost complete, particularly as we increasingly electrify our transport systems through electric vehicles, hydrogenfuel cells and biofuels – all potentially powered by energy sourced domestically.

Some parts of the transport sector – shipping and aviation – will be very difficult todecarbonise. Aviation will require the development of synthetic ‘drop-in’ fuels or low-carbon biofuel replacements, while shipping may move in the direction of small modular nuclear reactors (with minimal refuelling requirements). Even in these cases, however, there will be a diminishing reliance on imported fuels.

This will mean many nations will not only become increasingly fuel-independent for their electricity supply, but will also significantly decrease their dependence on energy supply chains for their transport systems.

The diminished importance of fossil fuel supply chains will gradually enhance national security for those nations currently subject to economic and geopolitical threats to their energy sources.

Supply chain interdiction will no longer be an option for nations wishing to control the sovereignty of other countries, and there will be fewer resource wars – as no country is likely go to war over another country’s wind and solar.

This process will be accelerated by international agreements to limit damaging climate change, which will eventually see a premium placed on carbon-based imports, and consequently on the proportion of embedded carbon-based energy.

A further driver will be continuing reductions in the cost of renewables, that, according to the August 2018 Photovoltaics Report by the Fraunhofer Institute for Solar Energy, have seen the price of solar panels fall by a factor of more than 100 in the last 37 years.

This convergence of overwhelming economics, the climate change imperative and national security enhancement will further drive the revolution in our energy systems.

Nevertheless, once the energy transformation has taken place, we will face different risks and opportunities presented by the new energy paradigm. We will have moved from a centralised generation system to a more complex network of disseminated renewable generation. Generator location will be driven largely by the geography of the best renewable resources.

This will be complemented bydisseminated storage (such as off‐river pumpedhydro and batteries), linked together by an augmented electricity transmission system, which will more closely resemble the Internet than a traditional network backbone.

In the same way that multiple redundancy and complex interconnectivity was designed into the Internet to enhance security of communication, this new Internet-of-Energy might also provide enhanced robustness by removing reliance on a few centralised generators and transmission lines.

Being able to re-route energy through a more strongly interconnected system, tap into a diversity of complementary energy sources distributed over a wide geographic region, and store energy for use in times of future need, could contribute to the flexibility and redundancy needed to ensure a more secure energy system – both for the reliability of domestic supply, and the ability to withstand attack from outside.

However, this also increases the vulnerability of the Internet-of-Energy due to the vastly increased number of access points open to cyber attack. For example, demand response (that is, load reduction to match supply) will be a major component of any future energy system, particularly to attenuate loads atpeak times – the equivalent to having analternative (negative) generation source.

Demand response may be implemented on an industrial scale, or could apply to millions of demand loads all the way down to the household level. This includes the ability to control individual household appliances through the Internet-of-Things– a prospect that will make the entiresystem vulnerable to attack at the weakest point in the demand response system.

Together with the increased points of attack through the disseminated energy generators themselves, and the more complex transmission and distribution networks, this will require a whole-of-system approach to cyber security in order to prevent one small component in the network taking down the entire system.

This is not just a potential threat. It is already a reality, as shown by events such as the 2012 cyber attack on the oil company, Saudi Aramco, as described by Christopher Bronk and Eneken Tikk‐Ringass in The Cyber Attack on Saudi Aramco, and the taking down of the Ukrainian electricity network in 2015, which is detailed in the Wired article, Inside the cunning, unprecedented hack of Ukraine’s power grid.

Woman poses with a sun at the #Time2Choose Sydney rally where people gathered to demand action to protect land, water and cultural heritage from the effects of coal mining and coal seam gas. (Photo credit: Kate Ausburn, CC BY 2.0).

It could be argued that even if the renewable energy revolution does not eventuate, a centralised fossil-fuel based system would also be vulnerable to cyber attack, particularly given that widespread demand response will inevitably become part of any electricity system.

There would be even greater vulnerability in such a centralised system if a single or multiple power station(s) could be selectively taken out, which could havecatastrophic effects on the stability of the entire network.

By comparison, the effect on system stability of removing multiple, small, disseminated renewable generators could potentially be more readily mitigated by delivering ancillary services to maintain voltage and frequency control, such as might be provided by widespread, disseminatedoff‐river pumped hydro and/or batteries.

Irrespective of this hypothetical comparison, the renewable technology train is speeding down the tracks and, at this moment, appears unstoppable. To ensure our energy systems in the coming years continue to deliver system reliability, the threat of cyber security needs to be addressed.

Potentially this may be made easier by the redundancy and diverse connectivity in a highly-disseminated, renewable energy network.

But no matter how the energy transformation develops, two other issues will need to be addressed.The first is the increased vulnerability of energy systems to extreme climatic events, the frequency of which is expected to increase with global warming.

This may be ameliorated to some extent by the robustness of a decentralised energy system, but we will still need measures to provide re-routing of network capacity, and ancillary services for voltage and frequency stability in a disseminated system.

The second issue is the decarbonisation of our energy systems, which must occur by mid-century to avoid the worst consequences of climate change. This may just be a stop-gap in our energy transformation until the advent of fusion power – the harnessing of the nuclear energy that powers the sun.

A march through St. Paul, Minnesota to protest using tar sands oil in favour of clean water and clean energy sources (photo credit: Fibonacci Blue, CC BY 2.0).

Already the International ThermonuclearExperimental Reactor (ITER) in Cardarache,France, which is funded by the major energy superpowers, is anticipated to demonstrate break-even around 2030. The engineering and physical scaling laws indicate that simply increasing the size of the reactor is all that is needed to achieve break-even: theITER project is expected to well‐exceed the threshold required.

If ITER is successful, the next project (DEMO, or DEMOnstration Power Station) will produce a demonstration commercial version of a fusion reactor that can run continuously. After 2050, large energy companies may supply fusion reactors to nations that have the technical capability to build and maintain them.

This will bring with it a new set of security issues, as the world potentially reverts once more to a centralised energy generating system, given that fusion reactors will be comparable to, or bigger than, the largest current thermal power stations.

Further security issues may arise because of the technological complexity of fusion power, which may mean a division between haves and have-nots in a future fusion world. We might therefore have to revisit this essay in a couple of decades’ time.

Finally, the unstoppable renewable energy train may eventually run right over the train-wreck graveyard of Australian climate and energy policy from the last decade.

The rest of the world has watched with, at best, bemusement as destabilisation by the Greens saw the demise of Labor’s Emissions Trading Scheme, the Abbott Government axed the carbon pricing mechanism, and politicalinfighting within the Coalition scuppered the first the Emissions Intensity Scheme,dumped the Clean Energy Target and buried its planned replacement, the National Energy Guarantee.

Now it may all become irrelevant until a future government decides to get on board the renewable energy train.

In the interim, it appears the increased capability of indigenous energy supply will enhance global geopolitical stability, andnetwork reliability will benefit from multipleredundancy and better connectivity in a disseminated Internet-of-Energy system. If weare sufficiently aware of the massive energytransformation that will take place, and act

in a timely manner to address the parallel threat of cyber security, then we may find ourselves living in a safer world in decades to come, increasingly free from disputes over energy supply and energy access.

Professor Ken Baldwin is Director of the Energy Change Institute at ANU, and Deputy Director of the Research School of Physics and Engineering. This essay was written as part of the ANU College of Asia and the Pacific’sParadigm_Shift: Securing our Energypublication.